This invention relates to a resilient vibration-dampening mounting which may be used to mount an operator station and an associated roll-over protective structure on a construction vehicle.
Operator stations of construction equipment and the like generally cover certain equipment necessary for operation of the vehicle. Failure of these equipments or maintenance required to be performed on these equipments may necessitate the removal of the operator station from the vehicle.
In any vehicle, whether it be a construction vehicle or material handling vehicle, vibration is imparted to the vehicle frame due to operation. In construction vehicles which may be operated over unimproved terrain, the vibration may be fatiguing to the operator if it is not dampened. Although normal seat padding may dampen some vibration, the remaining vibration may still reach the operator without additional dampening means in the mounting itself. Since vibration may affect instruments and the like, it has been found appropriate to isolate the entire operator's station from the vehicle frame through the use of resilient mountings.
Resilient mountings have taken many forms in view of the varying conditions under which they are utilized. In construction equipment, as noted previously, the operator's station, which is to be isolated from unwanted vibrations, should also be readily detachable from the vehicle; however, addition of the protective structures to the vehicle to prevent injury to the operator in the event of the vehicle rolling over has added considerable weight to the operator's station. The roll-over protective structure may also raise the center of gravity in addition to the added weight and therefore the whole operator's station may become unwieldy without mechanical means to pivotally move the operator's station away from the vehicle for maintenance. Such a structure is disclosed in application Ser. No. 614,812, now U.S. Pat. No. 4,053,178, assigned to the assignee of this invention.
In affixing a roll-over protective structure to a construction vehicle, it is necessary to take into account the vertical load imparted by the operator's station to which the roll-over structure may be affixed and which imparts a static load on any vibration-dampening element between the vehicle and the operator's station. The design must also take into account dynamic sideloads imposed upon the mounting structure in the event that the vehicle rolls over. By its very purpose, the roll-over protective structure must not fail during roll-over of the vehicle. Accordingly, it is appropriate to insure that the mounting is sufficiently strong to prevent failure because of dynamic sideloading during the roll-over period.
As previously noted, it is important to insure that a mounting for an operator's station and a roll-over protective structure is relatively easily disassembled. If the entire weight of the structure in a static condition is imparted to a horizontally oriented pin or bolt, it becomes necessary for the maintenance personnel to relieve the weight imparted to such a bolt before the bolt or pin may be removed. This is accomplished in earlier devices such as application Ser. No. 614,812 by providing a metal-to-metal contact and a locking pin positioned below the resilient mounting member so that the locking pin may be removed separately from the resilient mounting member. Although this structure is adequate, it must, of necessity, be massive.